自定义delegate 的运用实例

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace WebApplication1.core
{
    public delegate bool CompareHandler(DataParam p);
    /// <summary>
    /// 参数管理类
    /// </summary>
    public class DataParameter
    {
        public List<DataParam> DataParameters;
        public DataParameter()
        {
            DataParameters = new List<DataParam>();
        }

        /// <summary>
        /// 根据条件添加参数
        /// </summary>
        /// <param name="dataParam">要添加的参数</param>
        /// <param name="compare">添加参数要满足的条件</param>
        /// <returns>返回参数管理实例，实现联级添加</returns>
        public DataParameter AddParam(DataParam dataParam, CompareHandler compare)
        {
            if (compare(dataParam))
            {
                DataParameters.Add(dataParam);
            }
            return this;
        }

        /// <summary>
        /// 重载，添加参数
        /// </summary>
        /// <param name="dataParam">要添加的参数</param>
        /// <returns>返回参数管理实例，实现联级添加</returns>
        public DataParameter AddParam(DataParam dataParam)
        {

            DataParameters.Add(dataParam);

            return this;
        }

    }

    /// <summary>
    /// 参数
    /// </summary>
    public class DataParam
    {
        public DataParam(string name, System.Data.SqlDbType dtype, object value)
        {
            this.Name = name;
            this.DType = dtype;
            this.Value = value;
        }

        /// <summary>
        /// 参数名称
        /// </summary>
        public string Name { get; set; }

        /// <summary>
        /// 参数值
        /// </summary>
        public object Value { get; set; }

        /// <summary>
        /// 参数类型
        /// </summary>
        public System.Data.SqlDbType DType { get; set; }
    }
}
调用代码：
protected void Page_Load(object sender, EventArgs e)
{
    DataParameter instance = new DataParameter();
    DataParam item = new DataParam("fname", SqlDbType.VarChar, "wede");
    instance.AddParam(item, delegate(DataParam i) { return i.Name.Equals("fsname"); });
}
当然，也可以完全不用自定义delegate，而用Fun<DataParam,bool>代替delegate。